My winter thoughts

[tombo82685]

Well I promised this Friday night and well it's Sunday night, so here it is. 

So let me do a breakdown of what I like this year first.

1. Assuming we continue the descent of the qbo to negative sometime before mid january in the past has been a good indicator of high lat blocking. Last year the qbo was descending but then went back the other way and went positive, which may of been a reason why blocking failed last year.

2. We have a very low solar min this year, another possible indication of blocking. So far in late fall and start of December we have gotten a brief -nao period but more importantly the ao has been more often than not, negative. 

3. Just seems this year so far, that the warm ups are very brief, they are under producing. In bad winters, it always seems that the mild spells last longer while the cold spells are shorter than avg. This year it has been opposite.

4. SOI is actually nino, where as last year it didn't get truly to nino till late Jan/feb. 

5. MJO wise, due to the +IOD we have been getting numerous standing waves in in the phase 1-3 areas. Because of the strong convective properties in those phases it has produced a big subsidence zone in the warm phases. To me, with the coupling of the SOI, seems like the main base state this winter wants to be over Africa into IO then again around date line. While phases 1-3 are warmer in December as we progress through winter those phases become colder. 

6. SST, warm pool in GOA has usually correlated well to -epo outbreaks. We still have a modoki look going on in the tropical pacific.

7. Pulling this off Ton'y analogs, but when we get a warm october coupled with cold november it generally has been a colder than normal winter. Combine that with every october that has had a 90 in it ended up colder than normal.

8. Wet, very active pattern. Southern stream is a live and kicking. At some point with all the storminess you would think things break our way once or twice for a big storm

Now things that I don't like

1. The cooler water sitting off the west coast. Last month the pdo came in negative, not insanely negative, but negative. So i think we are going to deal with some bouts of poor pacific.

2. SST are a very close match to last year, which further may enhance some -pna periods for us. 

3. I know 13/14 was used as an analog, but if we use that as a base state this winter, with where the warm pool is in Alaska and further offshore from the west coast it will draw the conclusion main trough for winter could be to our west and we could deal with se ridge periods and cutters

 

So here is my snow map. i leaned a tiny bit above normal for most of the area esp central area on north and northeast. Reasoning for that is because I believe -epo will be a big player this year as well as good amount of miller b type systems. That all favors latitude. If we get extended periods of blocking, this whole snow map probably goes up in flames on the low side. Even though my positives out way my negatives by 3-1 almost, the pacific possibly being a pain this winter has me a little worried, so I didn't want to get to carried away. Regardless though, I don't see any huge flags for skunk winter right now. It's december and we are tracking snow threats even in a less than ideal pattern, so that is telling.  The best period to me is going to be late january into February as we get canoncial nino forcing and best chance for blocking. 

 

 

 

 

[snowlurker]

Very interesting, Tom. I've been anxious to hear your thoughts for some time now.

[Rainshadow]

I love a post that doesn't mention Barney once.  Which means, I really don't love this post.

[Chubbs]

Good write-up - I am going 35" for phl - because it worked for 90 degree days and per your list I'm positive.  To get 35" we are going to need at least one big one.

[chescowx]

Looks great Tom thanks!

I thought I would share an excerpt of my winter forecast that is being published this week in the East Nantmeal Sweetwater Reporter. Doubt there will be as many kudos as we give JB but....here goes

So, what does this portend for the upcoming winter season? Below is my forecast for 2019/2020 for East Nantmeal Township. with average temperature and snowfall estimates by month. To summarize regarding temperatures.  I see a slightly above normal December with a bit of a roller coaster. Cold to start warm up mid-month and turning cold by Christmas week. We generally have a 25% chance of a White Christmas with our last being in 2012. I do believe we have a chance of a White Christmas this year.  I expect a below normal and snowy January followed by a near normal but snowy February, a below normal March and an above normal April. Regarding snowfall I am forecasting around 51” of snowfall this winter season or about 14” above our seasonal average of 36.7”. Unlike the past few years I do think we see at least one or two major snowstorms with greater than 10” accumulations.

• December 2019 – Avg. Temperature 35.1 degrees (+1.5) above normal with Snowfall of 7.5” which is 2.8” above normal

• January 2020 – Avg. Temperature 27.7 degrees (-2.2) below normal with Snowfall of 19” or +8.1” above normal

• February 2020 – Avg. Temperature 32.9 degrees (+0.5) above normal with Snowfall of 17” or +4.8” above normal

• March 2020 – Avg. Temperature 38.9 (-1.4) below normal with Snowfall of 7” or +0.7” above normal

• April 2020 – Avg. Temperature 53.9 (+2.6) above normal with Snowfall of 0.5” or 0.6” below normal

[NEchestercountydude]

Thanks, Tom! Looks solid.